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In addition to a known alkaloid, some limonoids and coumarins, the new coumarins excavatins A–M have been isolated from Clausena excavata. Their structures have been assigned by NMR and CD investigations.

In addition to (−)-culantraramine and (−)-culantraraminol the bishordeninyl terpene alkaloids, (−)-culantraramine N-oxide, (−)-culantraraminol N-oxide and avicennamine, have been isolated from the leaves of Zanthoxylum avicennae. Their structures have been assigned by MS and especially by NMR investigations. © 1999 Elsevier Science Ltd. All rights reserved.

In addition to (-)-mehranine, hecubine, ibogaine, ibogaline, 19R-epi voacristine, 20-hydroxyconopharyngine and pedunculine the novel indole alkaloids 3-oxomehranine and 14α,15β-dihydroxy-N-methylaspidospermine have been isolated from the leaves and stems of Tabernaemontana bovina. The structure of 3-oxomehranine has been assigned by NMR investigations, the structure of 14α,15β-dihydroxy-N-methylaspidospermine by X-ray analysis and their absolute configurations by circular dichroism.

In addition to khasianine, solamargine, xylosylsolamargine and solasonine, three steroidal alkaloid glycosides, solasuaveoline, dihydrosolasuaveoline and isosolasuaveoline, have been isolated from aerial parts of Solanum suaveolens. The structures have been assigned by NMR investigations as (25R)-3 beta-{O-beta-D-glucopyranosyl-(1-->2)-O-beta-D- glucopyranosyl-(1-->4)-[O-alpha-L-rhamnopyranosyl-(1-->2)]-beta-D- galactopyranosyloxy}-22 alpha N-spirosol-5-ene, (25R)-3 beta-{O-beta-D-glucopyranosyl-(1-->2)-O- beta-D-glucopyranosyl-(1-->4)-[O-alpha-L-rhamnopyranosyl-(1-->2)]-beta-D - galactopyranosyloxy}-5 alpha, 22 alpha N-spirosolane and (25R)-3 beta-{O-beta-D-glucopyranosyl-(1-->6)-O- beta-D-glucopyranosyl-(1-->3)-[O-alpha-L-rhamnopyranosyl-(1-->2)]-beta-D - galactopyranosyloxy}-22 alpha N-spirosol-5-ene, respectively.

From the leaves of Ancistrocladus cochinchinensis, besides the already known ancistrocladinine, the new naturally occurring alkaloids, 6-O-methylhamateine, hamatinine, 6-O-methylhamatinine, 6-O-demethyl-7-epi-ancistrobrevine D, 7-epi- ancistrobrevine D and 6-O-demethyl-8-O-methyl-7-epi-ancistrobrevine D have been isolated and their structures elucidated from spectroscopic data and chemical degradation. © Elsevier Science Ltd. All rights reserved

In addition to solamargine, anguivine and isoanguivine, two new steroidal alkaloid glycosides, (23S)-23-hydroxyanguivine and (23S)-23-hydroxyisoanguivine, have been isolated from roots of Solanum uporo, the structures of which have been assigned by comparison with literature data as (23S,25R)-3 beta-[O-alpha-L-rhamnopyranosyl-(1-->2)-O- [beta-D-xylopyranosyl-(1-->3)]-beta-D-glucopyranosyloxy]-22 alpha N-spirosol-5-en-23-ol and (23S,25R)-3 beta-[O-alpha-L-rhamnopyranosyl-(1-->2)-O-[beta-D- xylopyranosyl-(1-->3)]-beta-D-galactopyranosyloxy]-22 alpha N-spirosol-5-en-23-ol.

In addition to 7-hydroxy-3-(4-hydroxybenzyl)-8-methoxychroman, 3-(4-hydroxybenzyl)-7,8-methylenedioxychroman, 7-hydroxy-3-(4-hydroxybenzyl)chroman, (±)-7,4′-dihydroxy-3′-methoxyflavan, (2 S )-7-hydroxyflavan, 4,4′-dihydroxy-2-methoxydihydrochalcone, 4,4′-dihydroxy-2′-methoxychalcone, 7,4′-dihydroxyflavone and (2 S )-7-hydroxyflavan-4-one, three new flavonoids have been isolated from the resin, called ‘dragon's blood’, of Dracaena cinnabari , the structures of which have been elucidated as 7-hydroxy-3-(3-hydroxy-4-methoxybenzyl)chroman, (2 S )-7,3′-dihydroxy-4′-methoxyflavan and 4-hydroxy-2-methoxydihydrochalcone.

In addition to some known chalcones and ecdysteroids three new chalcones have been isolated from aerial parts of Vitex leptobotrys , the structures of which have been identified as 2′,4′-dihydroxy-4,6′-dimethoxychalcone, 4′-hydroxy-4,2′,6′-trimethoxychalcone and 4,2′,4′, β -tetrahydroxy-6′-methoxy- α , β -dihydrochalcone, respectively.

Besides the known indole alkaloid, isovoacristine, the new bis-indole alkaloids, tabernaebovine and methylenebismehranine, have been isolated from the leaves and stems of Tabernaemontana bovina. Their structures have been assigned by NMR investigations.

From leaves of Ancistrocladus cochinchinensis , along with plumbagin, (+)-isoshinanolone, 3,3′-biplumbagin, 8,8′-biplumbagin, lupeol and betulin, three new tetralones have been isolated. Their structures were established as (2R∗, 4S∗)-4,5- dihydroxy-2-methyltetralone , (2R∗,4R∗)-4,5- dihydroxy-2-methyltetralone and (3R∗,4S∗)-3,4,8- trihydroxy-3-methyltetralone , respectively, by NMR spectroscopic data.

In addition to various eupomatenoids 2-(4-hydroxyphenyl)-5-(2-oxopropyl)-3-methylbenzo[ b ]furan and (2 R ,3 R )-2,3-dihydro-2-(4-hydroxyphenyl)-3-methyl-5-[( E )-1-propenyl]benzo[ b ]furan, three hitherto unknown constituents have been isolated from Caryodaphnosis tonkinensis . Their structures were elucidated by spectral methods as erythro -1-(3,4-methylenedioxyphenyl)-2-{4-[( E )-1-propenyl]phenoxy}propan-1-ol, 2-(4-hydroxyphenyl)-3-methylbenzo[ b ] furan-5-carbaldehyde and 1,2,3,3a,4,5,6,7,8,8a-decahydro-7-(1-hydroxy-1-methylethyl)-1,4-dimethylazulene-3a,8a-diol.

From the roots of Solanum abutiloides, solasodine, solafloridine and a new alkaloid have been isolated, the structure of which has been elucidated as 20-isosolafloridine [(20R,25R)-22,26-epiminocholest-22(N)-ene-3β,16α-diol]. The structure of an alkaloid from aerial parts of S. canense and S. fraxinifolium earlier supposed to be etioline has been recognized as 20,25-bisisoetioline [(20R,25R)-22,26-epiminocholesta-5,22(N)-diene-3β,16α-diol].

In addition to solamargine, isoanguivine and solasonine, two new steroid alkaloid glycosides, xylosyl-solamargine and xylosyl-β-solamarine, have been isolated from the aerial parts of Solanum coccineum, the structures of which have been elucidated as (25R)-3β-{O-β- d - xylopyranosyl -(1 → 2)-O-α- l - rhamnopyranosyl -(1 → 4)-O-[α- l - rhamnopyranosyl -(1 → 2)]-β- d - glucopyranosyloxy }-22αN- spirosol-5-ene and (25S)-3β-O-β- d - xylopyranosyl -(1 → 2)-O-α- l - rhamnopyranosyl -(1 → 4)-O-[α- l - rhamnopyranosyl -(1 → 2)]-β - d - glucopyranosyloxy }-22βN- spirosol-5-ene .

A new triflavonoid, damalachawin, was isolated from dragon's blood of Dracaena cinnabari. Its structure was established mainly by NMR spectroscopy.

From the bark of Caryodaphnosis tonkinensis three new polar eupomatenoids were isolated, for which the structures 5-(erythro-1,2-dihydroxypropyl)-2-(4-hydroxyphenyl)-3-methylbenzo[b]furan, 5-(erythro-1,2-dihydroxypropyl)-3-methyl-2-(3,4-methylenedioxyphenyl)benzo[b]furan and 5-(erythro-1,2-dihydroxypropyl)-2-(4-hydroxy-3-methoxyphenyl)-3-methylbenzo[b]furan were determined by spectral methods.

A new biflavonoid, cinnabarone, was isolated from dragon's blood of Dracaena cinnabari . Its structure was established, mainly by NMR spectroscopy, as a dihydrochalcone linked by a carbon-carbon bond to a deoxotetrahydrochalcone.

In addition to solamargine, two new steroid alkaloid glycosides, anguivine and isoanguivine, have been isolated from the roots of Solanum anguivi, the structures of which have been elucidated as (25R)-3 beta-[O-alpha-L-rhamnopyranosyl-(1--2)-O-[beta-D- xylopyranosyl-(1--3)]-beta-D-glucopyranosyloxy]-22 alpha N-spirosol-5-ene and (25R)-3 beta-[O-alpha-L-rhamnopyranosyl-(1--2)-O-[beta-D-xylopyranosyl- (1--3)-beta-D-galactopyranosyloxy]-22 alpha N-spirosol-5-ene.

In addition to tomatidine and soladulcidine, two new alkaloids, pimpifolidine and 22-isopimpifolidine, have been isolated from the roots of the wild tomato Lycopersicon pimpinellifolium , the structures of which have been elucidated as 22,26-epimino-16β,23-epoxy-5α,22αH,25αH-cholestane-3β,23α-diol and its 22βH-isomer.

In addition to diosgenin, tigogenin, tomatidenol, tomatidine, leptinidine, 5α,6-dihydroleptinidine, solasodine and soladulcidine, a new alkaloid has

The structure of an alkaloid isolated from the roots of Solanum robustum has been elucidated as N -hydroxysolasodine [(25 R )-22α N -spirosol-5-ene-3β, N -diol].

The structure of an alkaloid isolated from the roots of Solanum canense and S. fraxinifolium has been elucidated as (23S)-23-hydroxysolasodine [(23S,25R)-22α N-spirosol-5-ene-3β,23-diol].

Solamargine, solasonine, N-hydroxyrobustine and a new glycoalkaloid, N-hydroxysolamargine, has been isolated from the leaves of Solanum robustum, the structure of which has been elucidated as (25R)-3beta-{O-alpha-L-rhamnopyranosyl-(1-->2)-O-[alpha-L- rhamnopyranosyl- (1-->4)]-beta-D-glucopyranosyloxy}-22alphaN- spirosol-5-en-N-ol.

An alkaloid isolated from the roots of Lycianthes biflora has been identified as 2α-hydroxysoladulcidine [(25R)-5α,22α N -spirosolane-2α,3β-diol].

The ability of nicotianamine analogues to bring about the phenotypical normalization of the nicotianamine-auxotroph tomato mutant chloronerva is correlated with the co-ordination behaviour of the analogues towards transition metal ions. This is in agreement with the proposed metal ion carrier function of nicotianamine.

17,18-Didehydroloesenerine and 16,17-didehydroloesenerin-18-ol have been isolated from Maytenus loeseneri and their structures have been elucidated as ( R )-1-acetyl-8-[(1 Z ,4 Z )-1,4-heptadienyl]-1,5,9-triazacyclotridecan-6-one and (8 R )-1-acetyl-8-[(1 Z ,3 E )-5ξ-hydroxy-1-3-heptadienyl]-1,5,9-triazacyclotridecan-6-one, respectively.

The ‘normalizing factor’ for the mutant ‘chloronerva’ of the tomato, Lycopersicon esculentum cv Bonner Beste was shown to possess the structure (2 S :3′ S :3″ S )- N -[ N -(3-amino-3-carboxypropyl)-3-amino-3-carboxypropyl]-azetidine-2- carboxylic acid and proved to be identical with nicotianamine, especially on the basis of its high resolution mass and NMR spectroscopic investigations and those of some of its derivatives. It seems to be of general occurrence in vascular plants and has been isolated from Medicago sativa (Leguminosae) and Beta vulgaris (Chenopodiaceae) using a large-scale isolation procedure. Nicotianamine has an optimal molecular structure for chelating iron ions and is considered a possible phytosiderophore with an essential function in cellular iron transport and/or metabolism.

From leaflets of Spathelia wrightii a new pyranochromone has been isolated, the spectroscopic properties of which are in accordance with the structure 5-methoxy-2,2,8-trimethyl-10-senecioyl-2 H ,6 H -benzo(1,2-b, 5,4-b')dipyran-6-one ( 1 ).

Erythroculine, protostephanine and a new alkaloid have been isolated from Hyperbaena columbica , and the latter has been identified as 3-demethoxy-2